In an Asymmetrical Digital Subscriber Line (ADSL) modem and Speaker phone, echo cancellation (EC) technology has been widely used to improve quality of service (QoS) for end-users. For example, a typical line echo canceller (LEC) is generally used to remove electrical echoes due to reflections of hybrid components on a network where 2-line and/or 4-line conversions take place. Another type of echo canceller is an acoustic echo canceller (AEC) that may be used to remove acoustic echoes due to acoustic sound feedback from a speaker to a microphone on a hand-free speaker phone, mobile phone, or conference phone.
In the above examples of echo cancellers, and in types of present echo canceller technologies, substantially large processing power and high memory storage are required. For example, for RF echo cancellation technology in analogue domain that employs different kinds of filters, such as a finite impulse response (FIR), the use of large number of components such as down-converters that come with the use of the FIR filter consumes a substantial amount of device power.
As such, the designing of a system to implement the echo cancellation may require robust and careful adjustments to improve power savings and data transmission efficiency.